I've been trying to make a game for awhile and I wanted to do a hack but have no clue where to start, i've tried jedit but am having trouble I remember with my old pc it was easy but man its so hard with mac os x \, please you guys are my only hope.

The basic idea is to open a ROM binary and look for patterns that resemble the graphics in-game. You need to make sure you're in viewing it in "bit mode", so you can see the bit patterns of the graphics. Hex-editing isn't too useful for anything else other than graphics though, unless you know the location of bytes that control other things. Usually a disassembly of the ROM aids in that, but you need a decent understanding of assembly and the 2600's internal workings.

If you really want to do something substantial, find a game that already has a commented disassembly available, grab a copy of the DASM compiler, and start modifying code. That's what I did.

I got Hexedit and some patches to some arcade ROMs. The patches are suppose to fix bugs that result in kill screens or reset the machine. Since I didn't know what kind of programs patch ROM for Mac OS X. So I thought I could edit the hex values since I kind of read the memory locations. Okay, sounds like a good idea but ROMs get messed up. The Robotron fix at least playable but the game will reset at some point.